Antibacterial property of CuCrO2 nanopowders prepared by a self-combustion glycine nitrate process

• CuCrO2 nanopowders was prepared by low-temperature glycine nitrate process.
• 1250–1500 ppm of CuCrO2 nanopowders were found to depress the growth of Escherichia coli.
• Bulk powders by the solid state reaction exhibited no antibacterial property.
• The antibacterial property of nanopowders was attributed to rapid Cu ion releases.
• Heavy adhesion of nanopowders to bacteria also resulted in antibacterial property.

Porous CuCrO2 nanopowders were prepared via glycine nitrate process (GNP) at 175 °C in ambient air. The X-ray diffraction patterns showed a pure delafossite phase of CuCrO2 with numerous broad peaks, indicating a crystallite size of approximately 20 nm. The surface area of the CuCrO2 nanopowders was larger than 50 m2/g, nearly 100 times greater than that of bulk powders (0.47 m2/g). Pathogenic Gram-negative bacteria Escherichia coli (E. coli) were chosen as the antibacterial evaluation indicators for both the nanopowders and bulk powders. The results showed that 1750 ppm nanopowders inhibited the growth of E. coli. As a control, the bulk powders showed a normal growth profile. The antibacterial property of the CuCrO2 nanopowders can be attributed to the extremely large surface area, which induces rapid release of Cu ions and strong adhesion of nanopowders to bacteria.